Heretofore, there is known a battery provided with a battery case formed with a through hole such as a liquid injection port for injection of an electrolyte, this through hole of the battery case being hermetically sealed. Accordingly, batteries using various sealing structures to seal such a through hole have been proposed. For instance, Patent Document 1 discloses a sealed battery configured such that a seal material is interposed between an engagement flange of a sealing member and a circumferential outer surface of a liquid injection port (a through hole), in which a blind rivet is used as the sealing member.